Forced Gas Recirculation in Later Stage Refining Processes and Reactors

Abstract

In later stage hydrocarbon fuel refining processes involving cracking reactions for upgrading hydrocarbon containing feeds into liquid and gaseous hydrocarbon fuels, the ration of liquid to gaseous recovery is advantageously increased by forced recirculation of non-condensing gas into cracking reaction.

1 . A method, comprising:
 providing a hydrocarbon compound containing feed in a reaction vessel;   subjecting said feed to a cracking reaction in the reaction vessel;   removing vapors produced in the cracking reaction, said vapors removed through a reaction vessel outlet;   condensing a condensable fraction of the removed vapors to produce at least one liquid hydrocarbon; and   recycling non-condensing gases from the removed vapors back into the reaction vessel.   
     
     
         2 . The method of  claim 1 , wherein said recycling is at a volumetric flow rate exceeding a normal vapor exit volumetric flow rate, the normal vapor exit volumetric flow rate corresponding to the flow rate of vapor through the outlet that would be created by vapor production in the reaction vessel at said reaction conditions absent said recycling. 
     
     
         3 . (canceled) 
     
     
         4 . The method of  claim 2 , wherein said recycling comprises recycling only non-condensing gases. 
     
     
         5 . The method of  claim 4 , wherein said subjecting said feed to a cracking reaction comprises:
 heating the feed to temperatures of in the range of approximately 400-600° C.; and   controlling pressure to be in a range of approximately 0.5 to 70 psig.   
     
     
         6 . The method  claim 1 , wherein said recycling comprises continuously forcing the non-condensing gas back to the reaction vessel during the cracking reaction. 
     
     
         7 . (canceled) 
     
     
         8 . The method of  claim 6 , further comprising adding a reagent to the recycled non-condensing gas and enhancing reagent interaction in solid, liquid and gas phases in the cracking reaction by controlling the pressure at a level above approximately 3 bar. 
     
     
         9 . (canceled) 
     
     
         10 . The method of  claim 6 , further comprising condensing and removing water from the removed vapors. 
     
     
         11 . (canceled) 
     
     
         12 . The method of  claim 10 , further comprising controlling the temperature of the recycled gas below the temperature of the cracking reaction. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . A system for forced recirculation of gases in a reactor to improve liquid yields of hydrocarbon or hydrocarbon containing compounds or molecules, comprising an apparatus of a heated pressure vessel, means to recycle some of the exiting gases/vapor from the reactor, condensing system, multiple disengagement vessels, pressure and temperature gages and controls, condensed liquids storage, and piping connections therebetween. 
     
     
         25 . The system of  claim 24 , further comprising a mixer with a mixing blade extending into the pressure vessel to increase reaction kinetics to cause faster evolution of hydrocarbons from the liquid or solid phase during the cracking reactions. 
     
     
         26 . The system of  claim 24 , wherein said vessel is configured for temperatures of approximately 400-600° C. and pressures in the range of 0.5 to 70 psig. 
     
     
         27 . The system of  claim 24 , further characterized in that:
 an exit gas line branches off the recycle line at a point downstream from the means for control of the volumetric flow of non-condensing gas;   a control valve is disposed in the exit gas line to control pressure in the vessel; and   a pressure sensor is disposed in the vessel to control the control valve.   
     
     
         28 . The system of  claim 27 , further characterized in that a heat exchanger is disposed in the recycle line to control the temperature of non-condensing gases reintroduced to the vessel. 
     
     
         29 . The system of  claim 28 , further characterized in that the recirculated gas is injected into the vessel at an injection point diametrically spaced from the removal point of produced vapors. 
     
     
         30 . The system of  claim 29 , further comprising a control system including processor and memory means configured to execute control instructions comprising instructions for controlling the volumetric flow rate of recirculated gas into the vessel to exceed a normal vapor exit volumetric flow rate, the normal vapor exit volumetric flow rate corresponding to the flow rate of vapor exiting the vessel as would be created by vapor production in said vessel at the reaction conditions absent said recirculating. 
     
     
         31 . The system of  claim 30 , wherein the control system is further configured to execute instructions for:
 maintaining the temperature in the vessel to be in the range of approximately 400-600° C.;   maintaining the pressure in the vessel to be in a range of approximately 0.5 to 70 psig;   continuously forcing the non-condensing gas back to the reaction vessel during the cracking reaction.   
     
     
         32 . (canceled) 
     
     
         33 . (canceled) 
     
     
         34 . (canceled) 
     
     
         35 . (canceled) 
     
     
         36 . (canceled) 
     
     
         37 . The system of  claim 30 , wherein the control system is further configured to execute instructions for said maintaining the temperature of the recirculated gas below the temperature of the cracking reaction. 
     
     
         38 . (canceled) 
     
     
         39 . (canceled) 
     
     
         40 . (canceled) 
     
     
         41 . (canceled) 
     
     
         42 . (canceled) 
     
     
         43 . (canceled) 
     
     
         44 . A method of increasing the ratio of liquid to gaseous hydrocarbon fuels produced by subjecting a hydrocarbon containing feed to a hydrocarbon cracking reaction, removing vapors produced in the reaction and condensing condensable hydrocarbon vapors in the removed vapors to form liquid carbon fuels, characterized by recycling non-condensing gases from the cracking reaction back into the cracking reaction at a volumetric flow rate greater than a volumetric exit flow rate of vapors produced in the cracking reaction absent said recycling. 
     
     
         45 . The method of  claim 44 , further comprising controlling pressure in the cracking reaction to be in a range of approximately 1 to 3 bar. 
     
     
         46 . The method of  claim 44 , further comprising controlling the recycled gas temperature to be in the range of about 100-400° C. 
     
     
         47 . The method of  claim 44 , further comprising increasing evolution of hydrocarbon vapors from solid and liquid phases by mixing the feed during the cracking reaction to increase reaction kinetics. 
     
     
         48 . The method of  claim 44 , wherein said recycling comprises reintroducing the recycled gas to the cracking reaction at an injection point diametrically spaced from the removal point of produced vapors